A semiconductor integrated circuit (IC) connected to external ports is susceptible to electrostatic discharge damage from the operating environment. Electrostatic discharge occurs when electrical charge is rapidly transferred between one or more pins of the integrated circuit and an external object. The scaling-down of integrated circuits further increases the possibility of circuit damage from electrostatic discharges. Electrostatic discharge protection circuits may be used to shunt the electrostatic energy to protect sensitive core integrated circuits.
However, currently available electrostatic discharge protection circuits are either not robust enough to protect sensitive core circuits with smaller pattern feature size, require extra processing, or are not cost-effective.